Life is a bit easier when everything is in one place. Unfortunately, that isn’t possible with reviews. 

As each review site has unique forms for consumers to fill out and unique criteria for evaluation, there is not a way to import reviews to Google from other sources.

One option to combat this disconnect is to let your customers know that you would appreciate reviews on Google. This is becoming less of a problem day by day as Google is making it much easier for consumers to review businesses they have recently visited.